Process for breaking petroleum emulsions



Patented Nov. 11, 1941 PROCESS FOR BREAKING PETROLEUM EMULSIONS MelvinDe Groote, University City, and Bernhard Kaiser and Charles M. Blair,Jr., Webster Groves, Mo., assignors to Petrolite Corporation, Ltd.,Wilmington, Del., a corporation of Delaware No Drawing.

Application May 12, 1941,

Serial No. 393,128

4 Claims. (or. 252-344) This invention relates primarily to theresolution of petroleum emulsions, our present application being acontinuation, in part, of our copending application Serial No. 342,716,filed June of the water-in-oil type that are commonly re-' ferred to ascut oil, roily oil," "emulsified oil, etc., and which comprise finedroplets of naturally-occurring waters orbrines dispersed in a more orless permanent state throughout the oil which constitutes the continuousphase of the emulsion.

Another object of our invention is to provide an economical and rapidprocess for separating emulsions which have been prepared undercontrolled conditions from mineral oil, such as crude petroleum andrelatively soft waters or weak brines. Controlled emulsification andsubsequent demulsification under the conditions just mentioned is ofsignificant value in removing impurities, particularly inorganic salts,from pipeline oil.

Incidentally, a compound of the kind herein contemplated may be used asa break-inducer and for doctor treatment of the kind intended to sweetengasoline. See U. S. Patent No. 2,- 157,223, dated May 9, 1939, toSutton.

Such compounds may also find utility in recovering oil from subterraneanoil-bearing strata. See U. S. Patent No. 2,223,381, dated February 25,1941, to De Groote and Keiser.

. Compounds of the type herein contemplated are of particular value inpreventing water-inoil emulsions resulting from acidization ofcalcareous oil-bearing strata. See U. S. Patent No. 2,233,383, datedFebruary 25, 1941, to De Groote and Keiser. Such specific application ofdemulsifiers of the kind herein contemplated is disclosed in ourco-pending application Serial No. 393,129, filed May 12, 1941.

.The chemical compounds herein contemplated as demulsifying agents, areoxyalkyl derivatives of imidazolines. These types of materials and f themethod of preparing the same are well known.

For instance, see U. S. Patent No. 2,211,001, dated August 13, 1940, toChwala.

In our aforementioned co-pending application Serial No. 342,716, whichis concerned with various chemical compounds adapted for use in breakingoil field emulsions, reference was made to a type exemplified by thefollowing formula:

- NCH:

NH- Ha In regard to such compounds, it is pointed out in said co-pendingapplication Serial No. 342,716, that the oxyalkylated derivatives may beem.- ployed, This fact is stated in the followinglanguage:

Also, as is well known, any of the diamines of the kind previouslydescribed containing at least one amino hydrogen atom may be convertedinto hydroxylated derivatives by reaction with an alkylene oxide, suchas ethylene oxide, propylene oxide, glycidol, epichlorhydrin, and thelike. As to the general procedure employed, al-,

though not concerned particularly Withcycli amines or the like,reference is made to U. S.

Patent No. 2,046,720, datedJuly 7, 1936, to Bottoms.

The compounds herein contemplated are characterized by the presence of afive-membered heterocyclic ring with two atoms different from carbon.More specifically, they may be considered as derivatives of imidazole,frequently referred to as glyoxaline. Imidazole (glyoxaline) isindicated by the following formula:

f t m {12H As to the manufacture of imidazolines, reference is made tothe following patents: U. S. Patents Nos.' 2,215,861, 2,215,862,2,215,863 and 2,215,864, dated September 24, 1940, to Waldmann andChwala.

Imidazolines or glyoxalidines may be regarded as dehydration products ofcertain amides; and they may be obtained by reacting polyamines1,2-disubstituted'glyoxalidlne wherein R represents an alkyl or 'alkenylgroup containing from to carbon atoms (the resother acids, mixed higherfatty acids derived from animal or vegetable sources, for example, lard,cocoanut oil, rapeseed oil, sesame oil, palm kernel oil, palm oil, oliveoil, corn oil, cottonseed oil, sardine oil, tallow, soyabean oi peanutoil, castor oil, seal oils, whale oil, shark oil and other fish oils,teaseed oil, partially or completely hydrogenated animal and vegetableoils, such as these mentioned; hydroxy and alpha-hydroxy highercarboxylic, aliphatic and fatty acids, such as hydroxystearic acid,dihydroxypalmitic acid, dihydroxystearic acid, dihydroxybehenic acid.

. alphahydroxy capric acid, alphahydroxy stearic idue-of a higher fattyacid); R1 represents hy- 1 2,155,878, both dated April 25, 1939, t0Waldmann and Chwala.

The expression higher molecular weight carboxyacids is an expressionfrequently employed to refer to certain organic acids, particularlymonocarboxy acids, having more than six carbon atoms, and generally,less than 40 carbon atoms. The commonest examples include thedetergent-forming acids, i. e., those acidswhich combine with alkaliesto produce soap or soaplike bodies. The detergent-forming acids, inturn, include naturally-occurring fatty acids, resin acids, such asabietic acid, naturally-occurring petroleum acids, such as naphthenicacids, and carboxy acids produced by the oxidation of petroleum. As willbe subsequently indicated, there are other acids which have somewhatsimilar characteristics and are derived from somewhat difierent sources,and are different in structure, but can be included in the broad genericterm previously indicated.

Among sources of such acids may be mentioned straight chain and branchedchain, saturated and unsaturated, carboxylic, aliphatic, alicyclic,fatty, aromatic, hydroarmoatic, and aralkyl acids including caprylicacid, butyric acid, heptylic acid, caproic acid, capric acid, pimelicacid, sebacic acid, erucic acid, saturated and unsaturated highermolecular weight aliphatic acids, such asthe higher fatty acidscontaining at least eight" carbon atoms, and including, in addition tothose mentioned, melissic acid, stearic acid, oleic acid, ricinoleicacid, diricinoleic acid, triricinoleic acid, polyricinoleic acid,ricinostearolic "acid, ricinoleyl lactic acid, acetylricinoleic acid,chloracetyl-ricinoleic acid, linoleic acid, linolenic acid, lauric acid,myristic acid, undecylenic acid, palmitic acid, mixtures of any acid,alphahydroxy palmitic acid, alphahydroxy lauric acid. alphahydroxymyristic acid, alphahydroxy cocoanut oil mixed fatty acids, alphahydroxymargaric acid, alphahydroxy arachidic acid, and the like; fatty andsimilar acids derived from various waxes, such as beeswax, spermaceti,montan wax, Japan wax, coccerin, and carnauba wax. Such acids includecarnaubic acid, cerotic acid, lacceric acid, montanlc acid,psyllastearic acid, etc. As suggested, one may also employ highermolecular weight carboxylic acids derived, byoxidation and othermethods, from paraffin wax, petroleum and similar hydrocarbons; resinicand hydroaromatic acids, such as hexahydrobenzoic acid, hydrogenatednaphthoic, hydrogenated carboxy-diphenyl, naphthenic, and abietic acid;aralkyl and aromatic acids, such as hexahydrobenzoic acid, hydrogenatednaphthoic, hydrogenated ,poly carboxydiphenyl, naphthenic, and abieticacid; aralkyl and aromatic acids, such as benzoic 'acid, Twitchell fattyacids, naphthoic acid, carboxydiphenyl, pyridine carboxylic acid,hydroxybenzoic acid, and the like. 7

Other, suitable acids include phenylstearic acid, benzoylnonylic acid,campholicacid, fencholic acid, cetyloxybutyric acid, cetyloxyaceticacid, chlorstearic acid, etc. I

Another source of suitable acids are those commonly referred to as lacacids, such, for example, as the acids derived from shellac. Such acidsinclude various polyhydroxy acids, for example, aleuritic acid, shelloicacid, and kerrolic acid.

As is well known, one may use substituted acids in which some othernon-functional constituent enters the structure of the fatty acid. Forinstance, one may use aryl-, alkoxy-, ch1or-, keto-, andamino-derivatives. Generally speaking, however, it is always preferableto use the unsubstituted acid, particularly free from substituents whichcontain either oxygen or nitrogen atoms. Generally speaking, theintroduction of hydrocarbon radicals, regardless of source, has littleeffect, except in altering the hydrophile-hydrophobe balance.

One may also employ the blown or oxidized acids, such as blownricinoleic acid, blown oleic, etc., or estolides derived from blownoils, such as blown castor oil, blown soyabean oil. etc.

Needless to say, the acids themselves need not be employed;' but one mayreadily employ any two or more of the above mentioned acids orfunctional equivalent, such as the anhydride, the acyl chloride, or thelike. In some instances, the esters, especially in presence of a traceor a significant amount of water, act as the acid itself in that theacid is liberated. Unless specific reference is made to a particularisomer, one may employ any isomer or mixture of various isomers, if theacid or acids are so available. We have produced demulsifiers, for usein our process, by the following procedures:

hydroxy-.

, ing example.

Example 1 1-aminoethyl-2-heptadecenyl glyoxalidine is prepared by mixingone gram mole (282 grams) of oleic acid with two gram moles (206 grams)of diethylene triamine, and heating the mixture for a period of about 16hours under a distilling column. Water was continuously removed until atemperature of about 245 C. was reached. The quantity of water thusremoved amounted to about 1.7 moles. Unreacted diethylene triamine wasdistilled from the reaction mixture under vacuum, and the residue thenwas purified by distillation at an absolute pressure of 1 mm. ofmercury, at which point it boiled within a temperature range of 225 to250 C. About 220 grams of the 1-aminoethyl-2-heptadecenyl glyoxalidinewas obtained as a pale yellow liquid. The product also may bedesignated. by reference to the reactants used in its preparation, asoleyl diethylene triamine.

thylene' oxide is introduced into the above base at a temperature ofabout 120-140 C., un-

til the increase in weight amounts to about 2 pound moles of ethyleneoxide calculated upon one pound mole of the base.

Example 2 The base used in the preceding example is replaced byl-(aminoethyl ethylamino)-2-heptadecenyl glyoxalidine. This glyoxalidinewas prepared by reacting 1 gram mole of oleic acid with three gram moles(438 grams) of triethylene tetramine in a vessel equipped with adistilling column. The mixture was heated for a period of about sixhours, and water was continuously removed until a temperature of about300 C. was reached. Approximately 1.9 moles of water were thus removed.The reaction mixture was then distilled under vacuum to remove excesstriethylene tetramine. Ethylene oxide was employed in the same manner asin Example 1, preceding.

Eaample 3 Tetraethylenepentamineis substituted for triethylene tetramineas 'a reactant in the preced- The glyoxalidineobtained was treated asbefore with ethylene oxide.

Example 4 Lauric acid is substituted as a reactant for oleic acid in thethree preceding examples.

Example 5 Ricinoleic acid is substituted for oleic acid in Examples 1-3preceding.

Example 6 Naphthenic acid is substituted for oleic acid in Examples 1-3preceding.

Example 7 An equivalent molal amount of propylene oxide is substitutedfor ethylene oxide in Examples 1-6 within the scope of the claim.Similarly, where the claims specify the presence of the group i. e., thegroup introduced by oxyalkylation at the amino hydrogen .position, it isunderstood that R includes groups derived from glycid or the like.

It is to be noted that the compounds herein contemplated, being basic incharacter, maybe used as such, or in the form of a base, i. e., incombination with water, or in the form of a salt, i. e., in combinationwith an organic or inorganic acid, such as hydrochloric acid, aceticacid, lactic acid, and the like.

Specific attention is directed to the fact that one may use variousoxyalkylating agents in addition to those already indicated. Forinstance, note the oxyalkylating agents specifically enumerated inaforementioned U. S. Patent No.

2,211,001, and also in U. S. Patent No. 2,208,581,

dated July 23, 1940, to Hoefielmann. All the oxyalkylating agentsmentioned in both of the previously designated patents may be employedas reactants for the manufacture of demulsifying agents contemplated inthe present process.

Conventional demulsifying agents employed in the treatment of oil fieldemulsions are used as such, or after dilution with any suitable solvent,such as Water, petroleum hydrocarbons, such as gasoline, kerosene, stoveoil, a coal tar product, such as benzene, toluene, xylene, tar acid oil,cresol, anthracene oil, etc. Alcohols, particularly aliphatic alcohols,such as methyl alcohol, ethyl alcohol, denatured alcohol, propylalcohol, butyl alcohol, hexyl alcohol, octyl alcohol, etc., may beemployed as diluents. Miscellaneous solvents, such as pine oil, carbontetrachloride, sulfur dioxide extract obtained in the refining ofpetroleum, etc., may be employed as diluents. Similarly, the material ormaterials employed as the demulsifying agent of our process may beadmixed with one or more of, the solvents customarily used in connectionwith conventional demulsifying agents. Moreover, said material ormaterials may be used alone, or in admixture with other suitable wellknown classes of demulsifying agents.

It is well known that conventional demulsifying agents may be used in awater-soluble form, or in an oil-soluble form, or in a form exhibitingboth oil and water solubility. Sometimes they may be used in a formwhich exhibits relatively limited oil solubility. However, since suchreagents are sometimes used in a ratio of 1 to 10,000, or 1 to 20,000,or even 1 to 30,000, such an apparent insolubility in oil and water isnot significant, because said reagents undoubtedly have solubilitywithin the concentration employed. This same fact is true in regard tothe material or materials employed as the demulsifylng agent of ourprocess.

scribed will find comparatively limited application, so far as themajority of oil field emulsions are concerned; but we have found thatsuch a demulsifying agent has commercial value, as it will economicallybreak or resolve oil field emulconsisting of alicyclic hydrocarbonradicalaaiiphatic-hydrocarbon radicals, and aliphatic hydrocarbonradicals substituted by hydroxyl radiinto contact with or caused to actupon the emul I I sion to be treated, in any of the various ways, or

by any of the various apparatus now generally used to resolve or.break'petroleum emulsions,

with a chemical reagent, the above procedure being used either alone orin combinationwith other demulsifying procedure, such as the electricaldehydration process.

I The demulsifier herein contemplated may be employed in-connection withwhat is commonly I known-as down-the-hoie procedure, i. e., bring- .ingthe demulsifler in contact with the fluids oi the well ,atthebottom otthe'well, or at some point prior to their emergence.

the demulsifier is used in connection with acidifi- This particular.type or application isdecidedly feasible when cation of calcareousoil-bearing strata, especially I ii suspended in or dissolved in theacid employed for acidification.

What we claim as new and desire to' secure-L by Letters Patent is: r I

- I 1. A process for breakingpetroleum emulsions of the water-dn-oiltype, characterized by sub-y jecting the emulsiontto the action of ademulsi- -fier comprising oxyalkylated imidazolines substituted in2-positlon, by a radical containing.

from 11-22 carbon atoms selected from the group consisting of alicyclichydrocarbon radicals, aliphatic hydrocarbon radicals, andaliphatic'hydrocarbon radicals substituted by hydroxyl radicals; said oxalk lated imidazolines containin y y l I I g I drocarbon radicalssubstituted by hydroxyl radicals; said oxyalkylated vimidazolinescontaining the radical:

' --N--(RO)nH-; -NH--(R.O)nH

wherein R denotes an aliphatic radical and'n' is I a whole numbergreater than 2 and less than 11.-

'2, A process for breaking petroleum emulsions oi the water-in-oil type,characterized by subjecting the emulsion to the action of a demulsifiercomprising oxyalkylated imidazolines substituted in 2-position by aradical containing from ll-22 carbon atoms selected from the group lcals; said'oxyalkylated imidazolines'containing I the radical:

wherein R denotes an aliphatic radical and n is a whole number greaterthan 2 and less than 11;

said radical substituted in the 2-position being derived from a higherfatty acid. I

3. A process for breaking petroleum emulsions of the water-in-oil type,characterized by subjecting the emulsion to the action of a demuIsifiercomprising oxyalkylated imidazolines substituted in 2-position by aradical. containing from 11-22 carbon atoms selected from the groupconsisting of alicyclic hydrocarbonradicals, aliphatic hydrocarbonradicals, and aliphatic hydrocarbon radicals substituted by hydroxylradio cals; said oxyalkylated imidazolines containing thcradical: I I II I whereinR denotes an aliphatic radical and n is a whole numbergreater than 2 and less than;ll;'

said radical substituted-in the 2position being derivedfrom naphthenicacid.

4. A process for breaking petroleum emulsions oi the water-in-oil type,characterized by sub I jecting the, emulsion to. the action of adcinulsifler comprising oxyalkylated imidazolines; sub;

stituted in 2-position. by a radical containing :irom 1'1-22 carbonatoms selected from the group wherein R denotes an aliphatic radical andn is a consisting of alicyclic hydrocarbon radicals, aliphatichydrocarbon radicals, and aliphatic hythe radical:

